Replication of "The Politics of Aging: Age Difference in Welfare  Issue Salience in Japan 1972-2016" by Michio Umeda. 
* Description: This paper examines a factor affecting why the interests of the older electorate often prevail in politics in developed countries with aging populations, namely the difference in issue salience related to governmental programs for the elderly. Analysis of data collected with a national electoral survey in Japan conducted at every national election between 1972 and 2016 (28 surveys) revealed that elderly voters have been far more attentive - and more consistently attentive - to the welfare issue than the younger electorate when making voting choices. Moreover, the gap has grown in recent years as the population ages and the welfare program matures, probably due to policy feedback. This gap would enhance the influence of the elderly over the issue beyond their numbers and higher turnout, as discussed in previous studies. This result explains why welfare reform for the elderly has been very difficult, at least in Japan, despite (or, indeed, because of) considerable intergenerational inequality under the current system. At the same time, this result also shows that issue salience is not static but responds to media coverage, especially among young voters who would, otherwise, show less interest in the issue. In other words, lively public debate of the issue, covered by news media, can decrease the salience gap between the youth and the elderly. * Files included in this compressed replication package- replicationcode_PoliticsOfAgingUmeda_APR2020.R
- replicationdata_PoliticsOfAgingUmeda_APR2020.txt
- onlineappendix_PoliticsOfAgingUmeda_Apr2020.pdf

* Programs used to verify replication: 
- R 3.6.3

* Additional packages required:
- "lme4" package (https://cran.r-project.org/web/packages/lme4/index.html). 
- "arm" package (https://cran.r-project.org/web/packages/arm/index.html). 

* Additional packages used to verify replication:
- lme4: version 1-1-21, 13Apr2020
- arm: version 1.10-1, 13Apr2020

* Process of Replication:
(1) Download ReplicationPackage file
(2) Set the working directory, which should be the folder with this ReadMe file
(3) [R] Run Replication code.

* Most Recent Date of Successful Replication: April 13, 2019

* Codebook
-  refer to Table A2 in the "online appendix" file in the package. 

* Datasource
- 1972-2005: The Leviathan Data Bank run by Bokutaku-sha (URL http://www.bokutakusha.com/ldb/ldb_databank.html). 
- 2007-2016: The Social Science Japan Data Archive (URL http://csrda.iss.u-tokyo.ac.jp). 